Heat dissipation structure and electronic device adopting the same

ABSTRACT

A heat dissipation structure adapted to dissipate heat from a heat-generating structure includes a heat dissipation unit and a liquid metal layer. The heat dissipation unit includes a heat dissipation body and an anti-corrosion metal layer formed on the heat dissipation body. The liquid metal layer is disposed between the heat-generating structure and the anti-corrosion metal layer, and is opposite to the heat dissipation body. An electronic device that adopts the heat dissipation structure is also disclosed.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a Continuation of co-pending application Ser. No.17/240,411, filed on Apr. 26, 2021, for which priority is claimed under35 U.S.C. § 120; which claims priority of Taiwanese Utility Model PatentApplication No. TW109204988U filed on Apr. 27, 2020 and TaiwaneseUtility Model Patent Application No. TW110202467U filed on Mar. 9, 2021under 35 U.S.C. § 119, the entire contents of all of which are herebyincorporated by reference.

FIELD

The disclosure relates to a heat dissipation structure and an electronicdevice adopting the same, and more particularly to a heat dissipationstructure adapted to dissipate heat from a heat-generating structure andan electronic device adopting the same.

BACKGROUND

A liquid metal is a metal or a metal alloy that is in a liquid state atroom temperature due to its low melting point or that is in a liquidstate when heated to its melting point. Some examples of liquid metalinclude gallium indium tin alloy, indium bismuth tin alloy, and indiumbismuth zinc alloy. Liquid metals have high stability and exceptionalthermal and electrical conductivity. Moreover, the specific heatcapacity and thermal conductivity of the liquid metals are much higherthan those of the traditional silicone conductive pastes, so that theyare now used as a thermal conductive agent between a heat source andheat-dissipating fins or thermal modules.

Aluminum or copper is often used as the main material forheat-dissipating fins or thermal modules. However, aluminum is easilycorroded by gallium in the liquid metal, resulting in the damage of theheat-dissipating fins and losing the thermal conductivity of the liquidmetal. On the other hand, compared to aluminum, copper has a much stableelectron configuration due to the 10 electrons in its 3d orbital, andthus, copper does not corrode as easily as aluminum when in contact withgallium. Referring to FIG. 1 , in actual practice, after a period oftime and under high temperature, copper can still react with gallium toform a needle-like intermetallic compound CuGa, which is also known asliquid metal dry-out. This kind of intermetallic compound will continueto accumulate and thicken under long term use, as shown in FIGS. 2 to 4, and finally cause the liquid metal to lose its thermal and electricalconductivity. Further, if the liquid metal comes into contact with anelectronic component or substrate, it is also easy to cause shortcircuit damage.

SUMMARY

Therefore, an object of the present disclosure is to provide a heatdissipation structure and an electronic device adopting the same thatcan alleviate at least one of the drawbacks of the prior art.

According to a first aspect of the present disclosure, there is provideda heat dissipation structure adapted to dissipate heat from aheat-generating structure. The heat dissipation structure includes aheat dissipation unit and a liquid metal layer. The heat dissipationunit includes a heat dissipation body and an anti-corrosion layer formedon the heat dissipation body. The liquid metal layer is disposed betweenthe heat-generating structure and the anti-corrosion layer, and isopposite to the heat dissipation body.

According to a second aspect of the present disclosure, there isprovided an electronic device which includes a heat-generating structureand a heat dissipation structure. The heat dissipation structureincludes a heat dissipation unit and a liquid metal layer. The heatdissipation unit includes a heat dissipation body and an anti-corrosionlayer formed on the heat dissipation body. The liquid metal layer isdisposed between the heat-generating structure and the anti-corrosionlayer, and is opposite to the heat dissipation body.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the disclosure will become apparent inthe following detailed description of the embodiments with reference tothe accompanying drawings, of which:

FIG. 1 is a scanning electron microscope (SEM) image of a crystallinephase of a needle-like copper-gallium compound;

FIGS. 2 to 4 illustrate an accumulation process of the copper-galliumcompound;

FIG. 5 is a sectional view of a first embodiment of an electronic deviceaccording to the present disclosure;

FIG. 6 is a sectional view of a second embodiment of the electronicdevice of this disclosure;

FIG. 7 is a view similar to FIG. 6 , but illustrating how a blockingmember of the second embodiment works when a liquid metal layer of thesecond embodiment is squeezed;

FIG. 8 is a sectional view of a third embodiment of the electronicdevice of this disclosure;

FIG. 9 is a view similar to FIG. 8 , but illustrating how a blockingmember of the third embodiment works when a liquid metal layer of thethird embodiment is squeezed;

FIG. 10 is a sectional view of a fourth embodiment of the electronicdevice of this disclosure;

FIG. 11 is a sectional view of a fifth embodiment of the electronicdevice of this disclosure;

FIG. 12 is a sectional view of a sixth embodiment of the electronicdevice of this disclosure;

FIG. 13 is a sectional view of a seventh embodiment of the electronicdevice of this disclosure;

FIG. 14 is a view similar to FIG. 13 , but illustrating how a blockingmember of the seventh embodiment works when a liquid metal layer of theseventh embodiment is squeezed;

FIG. 15 is a sectional view of an eighth embodiment of the electronicdevice of this disclosure;

FIG. 16 is a top view of the eighth embodiment; and

FIG. 17 is a sectional view illustrating how the eighth embodimentprovides protection for the electronic device against corrosion byliquid metal.

DETAILED DESCRIPTION

Before the disclosure is described in greater detail, it should be notedthat where considered appropriate, reference numerals or terminalportions of reference numerals have been repeated among the figures toindicate corresponding or analogous elements, which may optionally havesimilar characteristics.

In the present disclosure, a heat dissipation structure 1 is providedfor dissipating heat from a heat-generating structure 2. The heatdissipation structure 1 includes a liquid metal layer 11 and a heatdissipation unit 12. The heat dissipation unit 12 includes a heatdissipation body 121 and an anti-corrosion layer 122 formed on the heatdissipation body 121. The liquid metal layer 11 is disposed between theheat-generating structure 2 and the anti-corrosion layer 122, and isopposite to the heat dissipation body 121. In some embodiments, theliquid metal layer 11 is in direct contact with the anti-corrosion layer122 of the heat dissipation unit 12.

In some embodiments, the heat dissipation body 121 may be made of, butnot limited to, copper, aluminum, and alloys thereof.

In some embodiments, the anti-corrosion layer 122 is plated on the heatdissipation body 121 to prevent direct contact between the liquid metallayer 11 and the heat dissipation body 121. In certain embodiments, theanti-corrosion layer 122 is made of metal or ceramic. The metal may be,but not limited to, nickel. Materials for the ceramic may be, but notlimited to, silicate, metal oxide (e.g., aluminum oxide, zinc oxide,beryllium oxide, or the like), metal nitride (e.g., aluminum nitride,boron nitride, silicon nitride, or the like), carbide (e.g., siliconcarbide, or the like), or metal hydroxide (e.g., aluminum hydroxide).The silicate may be made from feldspar, clay, quartz, or combinationsthereof.

In some embodiments, the heat dissipation structure 1 further includes ablocking member 13 that is connected to the anti-corrosion layer 122 andthat surrounds the liquid metal layer 11.

Referring to FIG. 5 , a first embodiment of an electronic device 3 thatadopts the heat dissipation structure 1 of this disclosure is provided.In this embodiment, the electronic device 3 includes the heatdissipation structure 1 and a heat-generating structure 2. Theheat-generating structure 2 includes a substrate 21, and an electroniccomponent 22 disposed on the substrate 21. The heat-generating structure2 may be, for example, but not limited to, a central processing unit(CPU) or a graphics processing unit (GPU). The substrate 21 includes aprinted circuit layer 211 located on top thereof, but is not limitedthereto.

The liquid metal layer 11 is disposed between the electronic component22 and the anti-corrosion layer 122, and is opposite to the heatdissipation body 121. In this embodiment, the liquid metal layer 11 iscoated on the electronic component 22, but is not limited thereto. Theliquid metal layer 11 may be coated on the anti-corrosion layer 122 oron both of the electronic component 22 and the anti-corrosion layer 122,as long as the liquid metal layer 11 is disposed between theheat-generating structure 2 and the heat dissipation unit 12. Further,in this embodiment, the anti-corrosion layer 122 is plated on the heatdissipation body 121, and is adhered to the liquid metal layer 11 so asto prevent the liquid metal layer 11 from directly contacting the heatdissipation body 121 during heat dissipation, thereby preventing theheat dissipation body 121 from being corroded by the liquid metal layer11 or forming an intermetallic compound therewith. Thus, damage of theheat dissipation body 121 can be avoided, and the heat dissipationstability of the liquid metal layer 11 can be ensured. Theanti-corrosion layer 122 of this embodiment is a nickel layer.

Referring to FIGS. 6 and 7 , a second embodiment of the electronicdevice 3 of this disclosure is substantially the same as the firstembodiment, except that the electronic device 3 of the second embodimentfurther includes a blocking member 13 that is disposed between thesubstrate 21 and the anti-corrosion layer 122, that is connected to theanti-corrosion layer 122, and that surrounds the liquid metal layer 11and the electronic component 22. The blocking member 13 is spaced apartfrom the electronic component 22, and may be disposed on the substrate21 by adherence, latching, or integrating with the substrate 21.Further, the blocking member 13 cooperates with the anti-corrosion layer122, the substrate 21, and the electronic component 22 to define areceiving space 100. Due to the fluidity of the liquid metal layer 11and when the liquid metal layer 11 is squeezed, a portion of the liquidmetal layer 11 may fall down onto the substrate 21, as shown in FIG. 7 .Under the aforesaid circumstance, the blocking member 13 can block andlimit the portion of the liquid metal layer 11 within the receivingspace 100, preventing the liquid metal layer 11 from short circuiting orcorroding other components of the electronic device 3.

Referring to FIGS. 8 and 9 , a third embodiment of the electronic device3 of this disclosure is substantially the same as the second embodiment,except that, in the third embodiment, the heat-generating structure 2further includes a plurality of electronic elements 23 disposed on thesubstrate 21 within the receiving space 100, and the electronic device 3further includes an insulation layer 31 that is disposed in thereceiving space 100 and that encapsulates the electronic elements 23.The electronic elements 23 may be capacitors or other components. Whenthe liquid metal layer 11 is squeezed, it will flow into a gap betweenthe insulation layer 31 and the anti-corrosion layer 122, as shown inFIG. 9 , and will not be in contact with the electronic elements 23.Thus, the electronic elements 23 are prevented from contacting with theconductive liquid metal layer 11 and short circuiting. The insulationlayer 31 may be an insulation paste or glue.

Referring to FIG. 10 , a fourth embodiment of the electronic device 3 ofthis disclosure is substantially the same as the second embodiment,except that the electronic device 3 of the fourth embodiment furtherincludes an insulation layer 31 that is disposed on the substrate 21 andthat surrounds the electronic component 22. When the liquid metal layer11 is squeezed, it will flow into a gap between the insulation layer 31and the anti-corrosion layer 122, and is prevented from contacting withthe substrate 21 or other components of the electronic device 3 andshort circuiting.

Referring to FIG. 11 , a fifth embodiment of the electronic device 3 ofthis disclosure is substantially the same as the fourth embodiment,except that the heat-generating structure 2 of the fifth embodimentfurther includes a plurality of electronic elements 23 that are disposedon the substrate 21, that surround the electronic component 22, and thatare encapsulated by the insulation layer 31.

Referring to FIG. 12 , a sixth embodiment of the electronic device 3 ofthis disclosure is substantially the same as the second embodiment,except that the electronic device 3 of the sixth embodiment furtherincludes an insulation layer 31 disposed on the substrate 21 within thereceiving space 100 and surrounding the electronic component 22. Whenthe liquid metal layer 11 is squeezed, it will flow into a gap betweenthe insulation layer 31 and the anti-corrosion layer 122, and isprevented from contacting with the substrate 21 or other components ofthe electronic device 3 and short circuiting.

Referring to FIGS. 13 and 14 , a seventh embodiment of the electronicdevice 3 of this disclosure is substantially the same as the firstembodiment, except that, in the seventh embodiment, the electronicdevice 3 further includes an insulation layer 31 that is disposed on thesubstrate 21 and that surrounds the electronic component 22, and theheat dissipation structure 1 further includes a blocking member 13connected between the insulation layer 31 and the anti-corrosion layer122 and surrounding the liquid metal layer 11 and the electroniccomponent 22. The blocking member 13 cooperates with the anti-corrosionmetal layer 122, the insulation layer 31, and the electronic component22 to define a receiving space 100. When the liquid metal layer 11 issqueezed, a portion of the liquid metal layer 11 will fall down onto theinsulation layer 31 within the receiving space 100, and is preventedfrom contacting with the substrate 21 or other components of theelectronic device 3 and short circuiting.

Referring to FIGS. 15 to 17 , an eighth embodiment of the electronicdevice 3 of this disclosure is substantially the same as the secondembodiment. However, in the eighth embodiment, the heat-generatingstructure 2 further includes at least one electronic element 23 that isdisposed on the substrate 21. The electronic device 3 of this embodimentfurther includes a fixing adhesive 32, an insulation layer 31, and astiffener ring 33. The stiffener ring 33 is disposed between thesubstrate 21 and the anti-corrosion layer 122, and is connected to thesubstrate 21. In certain embodiments, the stiffener ring 33 is disposedbetween the substrate 21 and the insulation layer 31. The at least oneelectronic element 23 is located between the electronic component 22 andthe stiffener ring 33. The fixing adhesive 32 is disposed on thesubstrate 21, and is located between the electronic component 22 and theelectronic elements 23. The insulation layer 31 extends from thestiffener ring 33 to the fixing adhesive 32, and divides the receivingspace 100 into an upper receiving portion 101 and a lower receivingportion 102. The upper receiving portion 101 is defined by theinsulation layer 31, a portion of the electronic component 22, theblocking member 13, and the anti-corrosion layer 122. The lowerreceiving portion 102 is defined by the insulation layer 31, the fixingadhesive 32, the stiffener ring 33, and the substrate 21. The fixingadhesive 32 and the at least one electronic element 23 are located inthe lower receiving portion 102, and are covered by the insulation layer31. The blocking member 13 is disposed and clamped between theinsulation layer 31 and the anti-corrosion layer 122. It should be notedherein that, in this embodiment, an insulation paste or glue 17 may beprovided in the lower receiving portion 102 and may encapsulate theelectronic elements 23 to enhance the effect of insulating the at leastone electronic element 23.

In this embodiment, the fixing adhesive 32 has a square shape, andsurrounds the electronic component 22, as shown in FIG. 16 . The fixingadhesive 32 is a polymeric material, preferably double-sided tape andwith an upper surface adhered to the insulation layer 31 and a lowersurface adhered to the substrate 21. The insulation layer 31 is aninsulation film. In this embodiment, the insulation layer 31 has aninner side connected to the fixing adhesive 32 and an outer sideconnected to the stiffener ring 33. Further, the insulation layer 31 islocated above the electronic elements 23 in order to cover the same. Incertain embodiments, the blocking member 13 is a polymeric material, andthe polymeric material may be a foam tape. In certain embodiment theblocking member 13 is a cushioning adhesive. The blocking member 13 hasa lower surface adhered to the outer side of the insulation layer 31 andan upper surface adhered to the anti-corrosion layer 122.

When the liquid metal layer 11 is squeezed and a portion thereof flowsdown onto the insulation layer 31 within the upper receiving portion101, as shown in FIG. 17 , the liquid metal layer 11 is prevented fromcontacting the electronic elements 23 and the substrate 21 through theblocking of the insulation layer 31, the blocking member 13, and thefixing adhesive 32, so that the electronic elements 23 and othercomponents of the electronic device 3 can be prevented from shortcircuiting and being damaged.

Installation and locations of the fixing adhesive 32, the insulationlayer 31, and the blocking member 13 are not limited to the disclosure,and can be subject to change according to the different configurationsof the heat-generating structure 2.

In view of the aforesaid, by forming an anti-corrosion layer 122 on theheat dissipation body 121 of the heat dissipation unit 12, theanti-corrosion layer 122 can prevent direct contact between the liquidmetal layer 11 and the heat dissipation body 121, so that reaction andcorrosion between the two can be avoided, thereby improving thestability and durability of the heat dissipation structure 1 of thisdisclosure. Moreover, by providing the blocking member 13 and theinsulation layer 31 in the electronic device 3, the liquid metal layer11 can be prevented from flowing out and damaging the electronic device3.

In the description above, for the purposes of explanation, numerousspecific details have been set forth in order to provide a thoroughunderstanding of the embodiment(s). It will be apparent, however, to oneskilled in the art, that one or more other embodiments may be practicedwithout some of these specific details. It should also be appreciatedthat reference throughout this specification to “one embodiment,” “anembodiment,” an embodiment with an indication of an ordinal number andso forth means that a particular feature, structure, or characteristicmay be included in the practice of the disclosure. It should be furtherappreciated that in the description, various features are sometimesgrouped together in a single embodiment, figure, or description thereoffor the purpose of streamlining the disclosure and aiding in theunderstanding of various inventive aspects, and that one or morefeatures or specific details from one embodiment may be practicedtogether with one or more features or specific details from anotherembodiment, where appropriate, in the practice of the disclosure.

While the disclosure has been described in connection with what areconsidered the exemplary embodiments, it is understood that thisdisclosure is not limited to the disclosed embodiment(s) but is intendedto cover various arrangements included within the spirit and scope ofthe broadest interpretation so as to encompass all such modificationsand equivalent arrangements.

What is claimed is:
 1. An electronic device (3), comprising: aheat-generating structure (2) including a substrate (21) and anelectronic component (22) disposed on said substrate (21); a heatdissipation structure (1) including a heat dissipation unit (12) thatincludes a heat dissipation body (121) and an anti-corrosion layer (122)formed on said heat dissipation body (121), and a liquid metal layer(11) disposed between said electronic component (22) and saidanti-corrosion layer (122) and opposite to said heat dissipation body(121); and an insulation layer (31) that is disposed on said substrate(21) and that surrounds said electronic component (22).
 2. Theelectronic device (3) as claimed in claim 1, wherein saidheat-generating structure (2) further includes at least one electronicelement (23) that is disposed on said substrate (21) , that is locatedbetween said electronic component (22) and said blocking member (13),and that is encapsulated by said insulation layer (31).
 3. Theelectronic device (3) as claimed in claim 1, wherein said anti-corrosionlayer (122) is made of metal or ceramic.
 4. The electronic device (3) asclaimed in claim 1, wherein said heat dissipation body (121) is made ofcopper, aluminum, or alloys thereof.